enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Relative dating - Wikipedia

    en.wikipedia.org/wiki/Relative_dating

    Relative dating by biostratigraphy is the preferred method in paleontology and is, in some respects, more accurate. [1] The Law of Superposition, which states that older layers will be deeper in a site than more recent layers, was the summary outcome of 'relative dating' as observed in geology from the 17th century to the early 20th century.

  3. Historical geology - Wikipedia

    en.wikipedia.org/wiki/Historical_geology

    Layers of rock, or strata, represent ... Historical geology makes use of relative dating in order to establish the sequence of geological events in relation to each ...

  4. Principle of original horizontality - Wikipedia

    en.wikipedia.org/wiki/Principle_of_original...

    The principle of original horizontality states that layers of sediment are originally deposited horizontally under the action of gravity. [1] It is a relative dating technique. The principle is important to the analysis of folded and tilted strata. It was first proposed by the Danish geological pioneer Nicholas Steno (1638–1686).

  5. Cross-cutting relationships - Wikipedia

    en.wikipedia.org/wiki/Cross-cutting_relationships

    Cross-cutting relationships can be used to determine the relative ages of rock strata and other structures. Explanations: A – folded rock strata cut by a thrust fault; B – large intrusion (cutting through A); C – erosional angular unconformity (cutting off A & B) on which rock strata were deposited; D – volcanic dike (cutting through A, B & C); E – even younger rock strata (overlying ...

  6. Law of included fragments - Wikipedia

    en.wikipedia.org/wiki/Law_of_included_fragments

    The law of included fragments is a method of relative dating in geology.Essentially, this law states that clasts in a rock are older than the rock itself. [1] One example of this is a xenolith, which is a fragment of country rock that fell into passing magma as a result of stoping.

  7. Stratigraphy - Wikipedia

    en.wikipedia.org/wiki/Stratigraphy

    Chronostratigraphy is the branch of stratigraphy that places an absolute age, rather than a relative age on rock strata. The branch is concerned with deriving geochronological data for rock units, both directly and inferentially, so that a sequence of time-relative events that created the rocks formation can be derived. The ultimate aim of ...

  8. Principle of faunal succession - Wikipedia

    en.wikipedia.org/wiki/Principle_of_faunal_succession

    This principle, which received its name from the English geologist William Smith, is of great importance in determining the relative age of rocks and strata. [1] The fossil content of rocks together with the law of superposition helps to determine the time sequence in which sedimentary rocks were laid down.

  9. Radiometric dating - Wikipedia

    en.wikipedia.org/wiki/Radiometric_dating

    Radiometric dating has been carried out since 1905 when it was invented by Ernest Rutherford as a method by which one might determine the age of the Earth. In the century since then the techniques have been greatly improved and expanded. [19] Dating can now be performed on samples as small as a nanogram using a mass spectrometer. The mass ...